Depot site clean-up complete

A MASSIVE operation to remediate the site of the former sewage treatment plant in South Grafton is now complete.

The clean-up, which started near the end of 2016, resulted in 72,000 tonnes of potentially contaminated material being transported via more than 2000 truck movements to a specialist disposal facility in Queensland.

Clarence Valley Council general manager, Scott Greensill, said the Environmental Protection Authority required former sewage treatment plants to be fully remediated.

"This was not a cheap exercise, but it was something we had to do," he said.

"Asbestos containing materials, biosolids and other contaminants had been dumped on the site over scores of years and there were few records of where and when that happened.

"That added to the difficulty of clean-up and to the cost."

Mr Greensill said the total cost was yet to be finalised, but was estimated to be $6.976 million.

"This will need to be funded from council's sewerage fund. It won't come from the general rate fund, so anything not related to sewerage will not be affected, but we will probably need to defer some capital projects that were planned to come from the sewerage fund to meet the costs," he said.

"It is important to stress that council had no choice but to remediate the site.

"When the new sewage treatment plant opened in Clarenza in 2010 it meant the old plant had to be cleaned up so council could surrender its licence to the EPA.

"Thankfully, that clean-up is now complete."

Mr Greensill said the completion of the clean-up meant council could now start work on a more efficient depot and close five existing depots in Grafton.

"That will operate in estimated operational savings of more than $1m annually," he said.